Although detailed pharmacokinetic studies have been performed on most major anticancer drugs currently in use, assays of drug concentration in plasma, cerebrospinal fluid and uring have not been routinely employed to determine variations in bioavailability and to adjust dosing accordingly. We wish through this grant to supply such data to supplement protocol drug trials conducted by the CALGB. Cytarabine levels achieved by several dosages and schedules of administration are currently being assayed. It is planned to follow this with drug level studies of platinum analogs, methotexate, adriamycin and vinca (Catharanthus) alkaloids to determine inter- and intrapatient variability, variations due to route or schedule, and their relationship of bioavailability to toxicity and to therapeutic benefit. These studies will use existing expertise and facilities within CALGB supported in sequence on priorities determined by the Chemotherapy Committee of CALGB.